Corrigendum - REACH24H Consulting Group

6.7.4.2.8.1 The reference holding time shall be determined by a method recognized by the competent
authority on the basis of the following:
(a) The effectiveness of the insulation system, determined in accordance with 6.7.4.2.8.2;
(b) The lowest set pressure of the pressure limiting device(s);
(c) The initial filling conditions;
(d) An assumed ambient temperature of 30 °C;
(e) The physical properties of the individual refrigerated liquefied gas intended to be
transported.
6.7.4.2.8.2 The effectiveness of the insulation system (heat influx in watts) shall be determined by type
testing the portable tank in accordance with a procedure recognized by the competent authority. This test
shall consist of either:
(a) A constant pressure test (for example at atmospheric pressure) when the loss of
refrigerated liquefied gas is measured over a period of time; or
(b) A closed system test when the rise in pressure in the shell is measured over a period of
time.
When performing the constant pressure test, variations in atmospheric pressure shall be taken
into account. When performing either tests corrections shall be made for any variation of the ambient
temperature from the assumed ambient temperature reference value of 30 °C.
NOTE: For the determination of the actual holding time before each journey, refer to 4.2.3.7.
6.7.4.2.9 The jacket of a vacuum-insulated double-wall tank shall have either an external design
pressure not less than 100 kPa (1 bar) gauge pressure calculated in accordance with a recognized technical
code or a calculated critical collapsing pressure of not less than 200 kPa (2 bar) gauge pressure. Internal and
external reinforcements may be included in calculating the ability of the jacket to resist the external pressure.
6.7.4.2.10 Portable tanks shall be designed and constructed with supports to provide a secure base
during transport and with suitable lifting and tie-down attachments.
6.7.4.2.11 Portable tanks shall be designed to withstand, without loss of contents, at least the internal
pressure due to the contents, and the static, dynamic and thermal loads during normal conditions of handling
and transport. The design shall demonstrate that the effects of fatigue, caused by repeated application of
these loads through the expected life of the portable tank, have been taken into account.
6.7.4.2.12 Portable tanks and their fastenings under the maximum permissible load shall be capable of
absorbing the following separately applied static forces:
(a) In the direction of travel: twice the MPGM multiplied by the acceleration due to
gravity (g) 1 ;
(b) Horizontally at right angles to the direction of travel: the MPGM (when the direction
of travel is not clearly determined, the forces shall be equal to twice the MPGM)
multiplied by the acceleration due to gravity (g) 1 ;
(c) Vertically upwards: the MPGM multiplied by the acceleration due to gravity (g) 1 ; and
(d) Vertically downwards: twice the MPGM (total loading including the effect of gravity)
multiplied by the acceleration due to gravity (g) 1 .
1 For calculation purposes g = 9.81 m/s 2 .
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